
.middle > div {
    border: 1px solid red;
}

.middle > div > div:first-child {
    color: orange;
    font-size: 30px;
    padding: 10px;
    border-bottom: 1px solid red;
}

.middle > div > div:nth-child(2) {
    padding: 10px;
    font-family: 新宋体;
    overflow: hidden;
}

.middle > div > div:nth-child(2) > div:first-child > div {
    margin: 30px 0;
    text-indent: 3em;
    line-height: 30px;

}

.middle > div > div:nth-child(2) > div:nth-child(2) {
    white-space: nowrap;
    overflow: hidden;
    animation: myfirst 5s linear infinite alternate;
}

@keyframes myfirst {
    0% {
        margin-left: 0;
    }

    28.5% {
        margin-left: 0;
    }

    33.3% {
        margin-left: -600px;
    }

    62% {
        margin-left: -600px;
    }

    66.7% {
        margin-left: -1200px;
    }

    95.2% {
        margin-left: -1200px;
    }

    100% {
        margin-left: 0;
    }
}